Editing Punched card (section)

=== Hollerith's early cards ===
[[File:Hollerith punched card.jpg|thumb|Hollerith card as shown in the ''[[Railroad Gazette]]'' in 1895, with 12 rows and 24 columns.<ref name="Railroad_1895"/>]]

[[Herman Hollerith]] was awarded three patents<ref name="USP395782"/> in 1889 for electromechanical [[tabulating machine]]s. These patents described both [[paper tape]] and rectangular cards as possible recording media. The card shown in {{US patent|src=uspto|395781}} of January 8 was printed with a template and had hole positions arranged close to the edges so they could be reached by a [[railroad conductor]]'s [[ticket punch]], with the center reserved for written descriptions. Hollerith was originally inspired by railroad tickets that let the conductor encode a rough description of the passenger:

{{blockquote|I was traveling in the West and I had a ticket with what I think was called a punch photograph...the conductor...punched out a description of the individual, as light hair, dark eyes, large nose, etc. So you see, I only made a punch photograph of each person.<ref name="Austrian_1982"/>{{rp|page=15}}}}

When use of the ticket punch proved tiring and error-prone, Hollerith developed the [[pantograph]] "keyboard punch". It featured an enlarged diagram of the card, indicating the positions of the holes to be punched. A printed reading board could be placed under a card that was to be read manually.<ref name="Truedsell_1965"/>{{rp|page=43}}

Hollerith envisioned a number of card sizes. In an article he wrote describing his proposed system for tabulating the [[1890 United States census|1890 U.S. census]], Hollerith suggested a card {{convert|3|by|5+1/2|in|cm}} of [[Manila paper|Manila stock]] "would be sufficient to answer all ordinary purposes."<ref name="Hollerith_1889"/> The cards used in the 1890 census had round holes, 12 rows and 24 columns. A reading board for these cards can be seen at the Columbia University Computing History site.<ref name="daCruz_2019_2"/> At some point, {{convert|3+1/4|by|7+3/8|in|0}} became the standard card size. These are the dimensions of the [[Federal Reserve Note#Large-size notes|then-current paper currency]] of 1862–1923.<ref name="Littleton"/> This size was needed in order to use available banking-type storage for the 60,000,000 punched cards to come nationwide.<ref name="daCruz_2019_2" />

Hollerith's original system used an ad hoc coding system for each application, with groups of holes assigned specific meanings, e.g. sex or marital status. His tabulating machine had up to 40 counters, each with a dial divided into 100 divisions, with two indicator hands; one which stepped one unit with each counting pulse, the other which advanced one unit every time the other dial made a complete revolution. This arrangement allowed a count up to 9,999. During a given tabulating run counters were assigned specific holes or, using [[relay logic]], combination of holes.<ref name="Hollerith_1889"/>

Later designs led to a card with ten rows, each row assigned a digit value, 0 through 9, and 45 columns.<ref name="Bashe-Johnson-Palmer-Pugh_1986"/> 
This card provided for fields to record multi-digit numbers that tabulators could sum, instead of their simply counting cards. Hollerith's 45 column punched cards are illustrated in [[Leslie Comrie|Comrie]]'s ''The application of the Hollerith Tabulating Machine to Brown's Tables of the Moon''.<ref name="Comrie_1932"/>